[SCSI] scsi_dh: Update RDAC device handler

This patch updates the RDAC device handler to
refuse to attach to devices not supporting the
RDAC vpd pages.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 94 insertions, 69 deletions

diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c
index 0e25a6e9c82..b093a501f8a 100644
--- a/drivers/scsi/device_handler/scsi_dh_rdac.c
+++ b/drivers/scsi/device_handler/scsi_dh_rdac.c
@@ -173,6 +173,11 @@ struct rdac_dh_data {
 #define RDAC_STATE_ACTIVE       0
 #define RDAC_STATE_PASSIVE      1
         unsigned char           state;
+
+#define RDAC_LUN_UNOWNED        0
+#define RDAC_LUN_OWNED          1
+#define RDAC_LUN_AVT            2
+        char                    lun_state;
         unsigned char           sense[SCSI_SENSE_BUFFERSIZE];
         union                   {
                 struct c2_inquiry c2;
@@ -182,6 +187,13 @@ struct rdac_dh_data {
         } inq;
 };
 
+static const char *lun_state[] =
+{
+        "unowned",
+        "owned",
+        "owned (AVT mode)",
+};
+
 static LIST_HEAD(ctlr_list);
 static DEFINE_SPINLOCK(list_lock);
 
@@ -197,9 +209,8 @@ static struct request *get_rdac_req(struct scsi_device *sdev,
 {
         struct request *rq;
         struct request_queue *q = sdev->request_queue;
-        struct rdac_dh_data *h = get_rdac_data(sdev);
 
-        rq = blk_get_request(q, rw, GFP_KERNEL);
+        rq = blk_get_request(q, rw, GFP_NOIO);
 
         if (!rq) {
                 sdev_printk(KERN_INFO, sdev,
@@ -207,17 +218,14 @@ static struct request *get_rdac_req(struct scsi_device *sdev,
                 return NULL;
         }
 
-        if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_KERNEL)) {
+        if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) {
                 blk_put_request(rq);
                 sdev_printk(KERN_INFO, sdev,
                                 "get_rdac_req: blk_rq_map_kern failed.\n");
                 return NULL;
         }
 
-        memset(&rq->cmd, 0, BLK_MAX_CDB);
-        rq->sense = h->sense;
-        memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
-        rq->sense_len = 0;
+        memset(rq->cmd, 0, BLK_MAX_CDB);
 
         rq->cmd_type = REQ_TYPE_BLOCK_PC;
         rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
@@ -227,12 +235,12 @@ static struct request *get_rdac_req(struct scsi_device *sdev,
         return rq;
 }
 
-static struct request *rdac_failover_get(struct scsi_device *sdev)
+static struct request *rdac_failover_get(struct scsi_device *sdev,
+                                         struct rdac_dh_data *h)
 {
         struct request *rq;
         struct rdac_mode_common *common;
         unsigned data_size;
-        struct rdac_dh_data *h = get_rdac_data(sdev);
 
         if (h->ctlr->use_ms10) {
                 struct rdac_pg_expanded *rdac_pg;
@@ -277,6 +285,10 @@ static struct request *rdac_failover_get(struct scsi_device *sdev)
         }
         rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
 
+        rq->sense = h->sense;
+        memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
+        rq->sense_len = 0;
+
         return rq;
 }
 
@@ -321,11 +333,10 @@ done:
 }
 
 static int submit_inquiry(struct scsi_device *sdev, int page_code,
-                unsigned int len)
+                          unsigned int len, struct rdac_dh_data *h)
 {
         struct request *rq;
         struct request_queue *q = sdev->request_queue;
-        struct rdac_dh_data *h = get_rdac_data(sdev);
         int err = SCSI_DH_RES_TEMP_UNAVAIL;
 
         rq = get_rdac_req(sdev, &h->inq, len, READ);
@@ -338,59 +349,68 @@ static int submit_inquiry(struct scsi_device *sdev, int page_code,
         rq->cmd[2] = page_code;
         rq->cmd[4] = len;
         rq->cmd_len = COMMAND_SIZE(INQUIRY);
+
+        rq->sense = h->sense;
+        memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
+        rq->sense_len = 0;
+
         err = blk_execute_rq(q, NULL, rq, 1);
         if (err == -EIO)
                 err = SCSI_DH_IO;
+
+        blk_put_request(rq);
 done:
         return err;
 }
 
-static int get_lun(struct scsi_device *sdev)
+static int get_lun(struct scsi_device *sdev, struct rdac_dh_data *h)
 {
         int err;
         struct c8_inquiry *inqp;
-        struct rdac_dh_data *h = get_rdac_data(sdev);
 
-        err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry));
+        err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry), h);
         if (err == SCSI_DH_OK) {
                 inqp = &h->inq.c8;
-                h->lun = inqp->lun[7]; /* currently it uses only one byte */
+                if (inqp->page_code != 0xc8)
+                        return SCSI_DH_NOSYS;
+                if (inqp->page_id[0] != 'e' || inqp->page_id[1] != 'd' ||
+                    inqp->page_id[2] != 'i' || inqp->page_id[3] != 'd')
+                        return SCSI_DH_NOSYS;
+                h->lun = scsilun_to_int((struct scsi_lun *)inqp->lun);
         }
         return err;
 }
 
-#define RDAC_OWNED      0
-#define RDAC_UNOWNED    1
-#define RDAC_FAILED     2
-static int check_ownership(struct scsi_device *sdev)
+static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h)
 {
         int err;
         struct c9_inquiry *inqp;
-        struct rdac_dh_data *h = get_rdac_data(sdev);
 
-        err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry));
+        err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry), h);
         if (err == SCSI_DH_OK) {
-                err = RDAC_UNOWNED;
                 inqp = &h->inq.c9;
-                /*
-                 * If in AVT mode or if the path already owns the LUN,
-                 * return RDAC_OWNED;
-                 */
-                if (((inqp->avte_cvp >> 7) == 0x1) ||
-                                 ((inqp->avte_cvp & 0x1) != 0))
-                        err = RDAC_OWNED;
-        } else
-                err = RDAC_FAILED;
+                if ((inqp->avte_cvp >> 7) == 0x1) {
+                        /* LUN in AVT mode */
+                        sdev_printk(KERN_NOTICE, sdev,
+                                    "%s: AVT mode detected\n",
+                                    RDAC_NAME);
+                        h->lun_state = RDAC_LUN_AVT;
+                } else if ((inqp->avte_cvp & 0x1) != 0) {
+                        /* LUN was owned by the controller */
+                        h->lun_state = RDAC_LUN_OWNED;
+                }
+        }
+
         return err;
 }
 
-static int initialize_controller(struct scsi_device *sdev)
+static int initialize_controller(struct scsi_device *sdev,
+                                 struct rdac_dh_data *h)
 {
         int err;
         struct c4_inquiry *inqp;
-        struct rdac_dh_data *h = get_rdac_data(sdev);
 
-        err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry));
+        err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry), h);
         if (err == SCSI_DH_OK) {
                 inqp = &h->inq.c4;
                 h->ctlr = get_controller(inqp->subsys_id, inqp->slot_id);
@@ -400,13 +420,12 @@ static int initialize_controller(struct scsi_device *sdev)
         return err;
 }
 
-static int set_mode_select(struct scsi_device *sdev)
+static int set_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h)
 {
         int err;
         struct c2_inquiry *inqp;
-        struct rdac_dh_data *h = get_rdac_data(sdev);
 
-        err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry));
+        err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry), h);
         if (err == SCSI_DH_OK) {
                 inqp = &h->inq.c2;
                 /*
@@ -421,13 +440,13 @@ static int set_mode_select(struct scsi_device *sdev)
         return err;
 }
 
-static int mode_select_handle_sense(struct scsi_device *sdev)
+static int mode_select_handle_sense(struct scsi_device *sdev,
+                                    unsigned char *sensebuf)
 {
         struct scsi_sense_hdr sense_hdr;
-        struct rdac_dh_data *h = get_rdac_data(sdev);
         int sense, err = SCSI_DH_IO, ret;
 
-        ret = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
+        ret = scsi_normalize_sense(sensebuf, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
         if (!ret)
                 goto done;
 
@@ -451,14 +470,13 @@ done:
         return err;
 }
 
-static int send_mode_select(struct scsi_device *sdev)
+static int send_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h)
 {
         struct request *rq;
         struct request_queue *q = sdev->request_queue;
-        struct rdac_dh_data *h = get_rdac_data(sdev);
         int err = SCSI_DH_RES_TEMP_UNAVAIL;
 
-        rq = rdac_failover_get(sdev);
+        rq = rdac_failover_get(sdev, h);
         if (!rq)
                 goto done;
 
@@ -466,9 +484,11 @@ static int send_mode_select(struct scsi_device *sdev)
 
         err = blk_execute_rq(q, NULL, rq, 1);
         if (err != SCSI_DH_OK)
-                err = mode_select_handle_sense(sdev);
+                err = mode_select_handle_sense(sdev, h->sense);
         if (err == SCSI_DH_OK)
                 h->state = RDAC_STATE_ACTIVE;
+
+        blk_put_request(rq);
 done:
         return err;
 }
@@ -478,38 +498,23 @@ static int rdac_activate(struct scsi_device *sdev)
         struct rdac_dh_data *h = get_rdac_data(sdev);
         int err = SCSI_DH_OK;
 
-        if (h->lun == UNINITIALIZED_LUN) {
-                err = get_lun(sdev);
-                if (err != SCSI_DH_OK)
-                        goto done;
-        }
-
-        err = check_ownership(sdev);
-        switch (err) {
-        case RDAC_UNOWNED:
-                break;
-        case RDAC_OWNED:
-                err = SCSI_DH_OK;
-                goto done;
-        case RDAC_FAILED:
-        default:
-                err = SCSI_DH_IO;
+        err = check_ownership(sdev, h);
+        if (err != SCSI_DH_OK)
                 goto done;
-        }
 
         if (!h->ctlr) {
-                err = initialize_controller(sdev);
+                err = initialize_controller(sdev, h);
                 if (err != SCSI_DH_OK)
                         goto done;
         }
 
         if (h->ctlr->use_ms10 == -1) {
-                err = set_mode_select(sdev);
+                err = set_mode_select(sdev, h);
                 if (err != SCSI_DH_OK)
                         goto done;
         }
-
-        err = send_mode_select(sdev);
+        if (h->lun_state == RDAC_LUN_UNOWNED)
+                err = send_mode_select(sdev, h);
 done:
         return err;
 }
@@ -606,11 +611,12 @@ static int rdac_bus_attach(struct scsi_device *sdev)
         struct scsi_dh_data *scsi_dh_data;
         struct rdac_dh_data *h;
         unsigned long flags;
+        int err;
 
         scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
                                + sizeof(*h) , GFP_KERNEL);
         if (!scsi_dh_data) {
-                sdev_printk(KERN_ERR, sdev, "Attach failed %s.\n",
+                sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
                             RDAC_NAME);
                 return 0;
         }
@@ -619,14 +625,33 @@ static int rdac_bus_attach(struct scsi_device *sdev)
         h = (struct rdac_dh_data *) scsi_dh_data->buf;
         h->lun = UNINITIALIZED_LUN;
         h->state = RDAC_STATE_ACTIVE;
+
+        err = get_lun(sdev, h);
+        if (err != SCSI_DH_OK)
+                goto failed;
+
+        err = check_ownership(sdev, h);
+        if (err != SCSI_DH_OK)
+                goto failed;
+
+        if (!try_module_get(THIS_MODULE))
+                goto failed;
+
         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
         sdev->scsi_dh_data = scsi_dh_data;
         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
-        try_module_get(THIS_MODULE);
 
-        sdev_printk(KERN_NOTICE, sdev, "Attached %s\n", RDAC_NAME);
+        sdev_printk(KERN_NOTICE, sdev,
+                    "%s: LUN %d (%s)\n",
+                    RDAC_NAME, h->lun, lun_state[(int)h->lun_state]);
 
         return 0;
+
+failed:
+        kfree(scsi_dh_data);
+        sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
+                    RDAC_NAME);
+        return -EINVAL;
 }
 
 static void rdac_bus_detach( struct scsi_device *sdev )
@@ -645,7 +670,7 @@ static void rdac_bus_detach( struct scsi_device *sdev )
                 kref_put(&h->ctlr->kref, release_controller);
         kfree(scsi_dh_data);
         module_put(THIS_MODULE);
-        sdev_printk(KERN_NOTICE, sdev, "Detached %s\n", RDAC_NAME);
+        sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", RDAC_NAME);
 }